Making sense of multiple sclerosis

Multiple Sclerosis is a common disease which attacks the brain and spinal cord . . .

Multiple sclerosis or MS is a disease in which the nerves of the brain and spinal cord (the central nervous system or CNS) are damaged by one’s own immune system, thus making it an autoimmune disorder.

The CNS is made up of nerves that are covered by a fatty substance called myelin, which insulates the nerves and helps with the transmission of nerve impulses. In MS the myelin is destroyed (demyelination). As a result of this destruction, scar tissue is built up (sclerosis) in the brain and spinal cord. This process of demyelination and scar tissue formation disrupts the electrical signals transmitted in the brain and spinal cord. It is this disruption of communication that causes the symptoms of MS.

MS affects approximately 400,000 American. It is nearly three times more common in women, and it occurs more frequently in Caucasians — and rarely occurs before adolescence. The risk of developing MS increases from teen years to age 50, then the risk gradually declines.

It’s not fully understood what causes MS. Research suggests that the environment, genetics and perhaps a virus play a role. MS is a disease of temperate climates — its prevalence increases with distance from the equator. The disease is common in Scandinavia, Scotland and northern Europe. MS may, in part, be inherited. First-, second- and third-degree relatives are at higher risk. Siblings of an affected person have a 2-5% risk of developing MS. Researchers theorize that people may have a genetic predisposition and then react to some environmental agent leading to an autoimmune response.

Symptoms. The defining feature of MS is that symptomatic episodes occur months or years apart and affect different anatomic locations, hence the description “separated in time and space.” The presentation of symptoms of MS varies among patients.

• Muscle symptoms: weakness, stiffness, feeling of heaviness in limbs, clumsiness
• Sensory symptoms: tingling, pins and needles, numbness, feeling of electricity moving down your back and limbs
• Visual symptoms: blurry, hazy or double vision; 20% of patients first present with optic neuritis which is characterized by loss of vision or color vision in the affected eye and pain on eye movement
• Fatigue: reported by at least 75% of sufferers
• Cognitive dysfunction: may include speech, memory, attention, problem solving, abstract reasoning

Diagnosis. Making the diagnosis can be difficult because there is no single diagnostic test. The diagnosis is best made by a neurologist. Specific criteria have been developed to help diagnose MS.

A simplified summary of the criteria includes symptoms and signs indicating disease of the brain and spinal cord, two or more episodes lasting at least 24 hours and occurring at least one month apart, and evidence of two or more lesions on MRI.

Treatment. Acute exacerbations are frequently managed with steroid treatment, often intravenously. If steroids do not work or are contraindicated, plasma exchange (plasmapheresis) may be helpful. Neither steroids nor plasmapheresis change the overall disease progression. A number of approved drugs reduce the frequency and severity of attacks and may reduce the accumulations of lesions in the brain and spinal cord. These agents target the immune system.

Course of illness. Multiple sclerosis is different for every person. It can range from only causing minor intermittent problems or may become seriously disabling. There are general courses of MS:

• Relapsing-remitting: symptoms fade and then return on and off for many years
• Secondary progressive: first starts out as relapsing-remitting and then becomes “progressive,” getting steadily worse
• Primary progressive: symptoms are progressive from the start
• Progressive relapsing: symptoms come and go but nerve damage gets steadily worse

If you would like more information about multiple sclerosis or an appointment with a specialist, please call or email us today. For more information on MS, click here.

SUSAN LOCKE, MD, is Healthnetwork Foundation’s medical director.

Healthnetwork is a Legatus membership benefit, a healthcare “concierge service” that provides members and their families access to some of the most respected hospitals in the world. One Call Starts It All: (866) 968-2467 or (440) 893-0830. Email: [email protected]